This is a note to let you know that I've just added the patch titled

cifs: Fix autonegotiate security settings mismatch

to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: cifs-fix-autonegotiate-security-settings-mismatch.patch and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From 9aca7e454415f7878b28524e76bebe1170911a88 Mon Sep 17 00:00:00 2001

From: Daniel N Pettersson danielnp@axis.com Date: Thu, 11 Jan 2018 16:00:12 +0100 Subject: cifs: Fix autonegotiate security settings mismatch

From: Daniel N Pettersson danielnp@axis.com

commit 9aca7e454415f7878b28524e76bebe1170911a88 upstream.

Autonegotiation gives a security settings mismatch error if the SMB server selects an SMBv3 dialect that isn't SMB3.02. The exact error is "protocol revalidation - security settings mismatch". This can be tested using Samba v4.2 or by setting the global Samba setting max protocol = SMB3_00.

The check that fails in smb3_validate_negotiate is the dialect verification of the negotiate info response. This is because it tries to verify against the protocol_id in the global smbdefault_values. The protocol_id in smbdefault_values is SMB3.02. In SMB2_negotiate the protocol_id in smbdefault_values isn't updated, it is global so it probably shouldn't be, but server->dialect is.

This patch changes the check in smb3_validate_negotiate to use server->dialect instead of server->vals->protocol_id. The patch works with autonegotiate and when using a specific version in the vers mount option.

Signed-off-by: Daniel N Pettersson danielnp@axis.com Signed-off-by: Steve French smfrench@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- fs/cifs/smb2pdu.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)

--- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -585,8 +585,7 @@ int smb3_validate_negotiate(const unsign }

/* check validate negotiate info response matches what we got earlier */ - if (pneg_rsp->Dialect != - cpu_to_le16(tcon->ses->server->vals->protocol_id)) + if (pneg_rsp->Dialect != cpu_to_le16(tcon->ses->server->dialect)) goto vneg_out;

if (pneg_rsp->SecurityMode != cpu_to_le16(tcon->ses->server->sec_mode))

Patches currently in stable-queue which might be from danielnp@axis.com are

queue-4.9/cifs-fix-autonegotiate-security-settings-mismatch.patch